Combined engine starter and generator



March 21, 1939-. E. SCHAEREN I COMBINED ENGIN E STARTER AND GENERATOR 4 Sheets-Sheei. 1

Filed Aug. 31; 195'! Elsi March 21,1939. E. SCHAEREN 2,151,437

CGMBINED ENGINE STARTER AND GENERATOR Filed Aug. 31, 1937 4 Sheets-Sheet 2 Invenfor:

March 21, 1939. E. SCHAEREN 2,151,437

COMBINED ENGINE STARTER AND GENERATOR Filed Aug. 31. '19s? 4 Sheets-Sheet 3 March 21, 1939. E. SCHAEREN COMBINED ENGINE STARTER AND GENERATOR 4 Sheets-Sheet 4 Filed Aug. 31. 1937 Patented Mar. 21, 1939 PATENT OFFICE COMBINED ENGINE s'ran'rna AND' oam-zaa'roa Ernst Schaeren, Soleure, Switzerland, assignor to Scintilla, Ltd Solenre, Switzerland, a corporation of Switzerland Application August 31, 1937, Serial No. 161,859 In Switzerland September 4, 1936 20 Claims.

This invention relates to electric motor and generator apparatus, and more particularly to electric starting and generating apparatus for internal combustion engines.

One of the objects of the invention is to provide an apparatus of this kind comprising a single dynamo electric machine adapted to function both as a motor and as a current generator, in which said dynamo electric machine is enabled to runat full speed and full'power as a starting motor for the internal combustion engine without being compelled to run unduly fast when driven by the latter running at full speed.

Another of the objects of the invention is to provide means for changing the speed ratio be: tween the internal combustion engine and the dynamo electric machine without engaging and disengaging gear members, ratchets, dental clutches and similar coupling means which are likely to cause shocks in the drive.

A further object of the invention is to provide means for automatically effecting in the correct sequence the several control steps necessary for operating such apparatus, and for preventing the latter from being damaged by improper opera tion.

With this general statement of the objects and purposes of my invention, I shall now proceed to describe one embodiment thereof and the manner in which my invention may be carried out, and it will be understood that while I have described what may be considered as preferable embodiments of my invention; I do not limit myself to the precise features, herein set forth, as they may be varied by those skilled in the art in accordance with the particular purposes for which they are intended and the conditions under-which they are to be utilized.

In the drawings, Fig. 1 shows, partly in longitudinal section, the dynamo electric machine with the wheel gear, the electric connections and terminals being omitted.

Fig. 2 is a cross-section on the line A-A of Fig. 1.

Fig. 3 is another cross-section on the line BB.

Fig. 4 shows a detail of Fig. 1 on a larger scale. 5 is a cross-section on the line CC of Fig. 6, a cross-section on the line D-D of Fig. 1.

Fig. '7 is a diagram of the electric connections of the installation shown in Figs. 1 to 6.

Fig. 8 represents a further embodiment of the invention.

Fig. 9 is a diagram of the electric connections of the installation according to Fig. 8.

In the embodiment-shown in Figs. 1 to '7 the dynamo electric machine has a field-winding l fixedly mounted in the casing 2 and a rotating armature shaft 3 carrying the amature 4 and the commutator 6 connected to the armature 5 winding 5. The pinion support I which is keyed to the shaft 3 carries a journal 8 supporting a pair of pinions 9 and I0 loosely rotatable thereon but rigidly connected to one another. The pinion 9, of larger diameter, meshes with the in- 10 ternal teeth ll of a drum l2, and the pinion ID, of smaller diameter, meshes with the internal teeth l3 of a wheel M. The hub l5 of the latter is rotatably supported by a bearing mounted in the end plate 16, and is journalled on the armature shaft 3. It is in driving relation with the internal combustion engine by means of an elastic coupling and a drive shaft l8. The said elastic coupling consists of an internal part I! keyed to the hub l5 and carrying abutments 35, and a housing 36 integral with the shaft I8 and having abutments 31. These abutments 35 and 31 are arranged to form spring seats for the compression springs 38 which trans- 'mit the turning moment between the hub I5 and the housing 36.

The drum I2 is supported by and freely rotatable on' the armature shaft 3 and the hub l5, and can be coupled with the wheel H by means of. a coupling device controlled by a stationary electromagnet l9. This coupling device or electro-magnetic clutch operates as a friction clutch and consists of a disc 20 provided with a friction facing, which disc is mounted to turn with the drum l2 by pins 2| and held away from the'35 bottom of the drum l2 and into contact with the wheel by springs 22. The armature plate 23 connected to the disc 20 by the pins 2| is subject to the attraction of the eiectromagnet l9 when the latter is energized so that'its movement un Zw couples thedrum l2 from the wheel H. The drum l2 may be arrested with reference to the gear casing 25 by means of the friction brake 24 which is actuated by an electromagnet' 28 when the latter is energized.

The armature shaft 3 of the electric machine carries a centrifugal switch 58 (Fig. '7, also Figs. 1 and 3) which comprises a weight 21 mounted to turn with the shaft 3 bymeans of the guide 28 and radially displaceable against the resistance of the spring 29 which is under a suitable initial compression. The centre of gravity of said I weight 21 is eccentrically located with reference to the axis of the shaft 3. Rotatably mounted on thecasing cover 30 is a ring 3| carrying a switch 5 cooperating stationary contact 34 by the spring 33 in the direction opposite to the direction of rotation of the shaft 3.

The electrical connections of the installation shown in Fig. '7 will now be explained: The starting circuit leads from one pole of the storage battery 40 through a pair of contacts 4i controlled by the switch 42 to the winding 43 of the dynamo electric machine. This winding forms a part of the field winding l and is connected in series with the winding 5 of the armature 4. The starting circuit is completed through ground connection 44. A shunt winding 49 also generating the field winding i assists the winding 43 in its eflect.

The main circuit of the generating operation of the dynamo electric machine leads from the terminal 45 through current coils 5i and 48 to an automatic switch 46 of known construction. This switch is under the influence of a potential coil 41 which is energized according to the potential delivered by the dynamo electric machine and closes the circuit only when said potential exceeds a definite minimum value. The switch 48 is also under the influence of a current energized according to the flow of current through the armature 4. This current coil interrupts the circuit whenever the current reverses through the latter. whereby the battery would be discharged. From the switch 4l,-the circuit leads to ground 44 through the battery ll which in this instance is the load. Additional current consuming deresistance ll.

vices not shown in the drawings, e. g. the ignition system of the internal combustion engine, a light in: installation etc. may be connected in parallel with the battery 4|.

The fleid winding 4! used for the generator operation of the dynamo electric machine is connected in parallel, with the winding of the armature 4 and is controlled by an automatic regulator. This regulator controls the excitation of the dynamo electric machine in known manner under the influence of the currents flowing through current coil II and a potential coil 52, by opening and closing a pair oi contacts I! shunted by a The circuits of the two electromagnets IQ for actuating the clutch and 2B for actuating the brake, have a common connection 53 comprising a further pair of contacts 54 controlled by a multi-pole switch 42. Thus both said electromagnets are always connected in circuit at the same time, and the interruption of the current for the clutch electromagnet simultaneously causes interruption of the current for the brake electromagnet. Consequently the coupling of the drum I 2 with the wheel I 4 causes release of the brake 24, and the arresting of the drum by means of the brake causes its uncoupling from the wheel i 4. The circuit of the brake electromagnet also includes the above described centrifugal switch 58. g

The switch 42 is electromagnetically actuated by means of the coil 55. In addition to a manually operated switch 56, the circuit of this coil includes an auxiliary switch 51 which is coupled to the automatic switch 46 in such a way that it keeps the circuit of the coil ll interrupted so long as the switch 46 is closed.

The operation of the mechanism just described is as follows: In starting the internal combustion engine the manually operated switch 58 is closed, so that current flows through the coil 55 to operate the switch 42 and thus to close the coil 48 which is 2,161,487 contact 32. The latter is pressed against the two electromagnet circuits at the contacts I4. Consequently the electromagnets 26 and I! are energized, and the drum i2 is arrested by means of the brake 24 and at the same time uncoupled from the wheel l4. The switch 42 also closes the starting circuit of thedynamo electric machine at the contacts 4|. The armature 4 begins to rotate and with it the pinion support "I carried by the shaft 3. The pinion 8 rolls along the toothed rim ll of the arrested drum l2, and the smaller pinion Ill revolving with the pinion I imparts to the wheel l4 and therefore to the shaft I8 a rotating movement of considerably reduced speed as compared with that of the shaft 3.

When the internal combustion engine starts, it accelerates the rotation of the armature 4. When a definite speed of rotation is exceeded the centrifugal force acting upon the flyweight 21 of the centrifugal switch overcomes the initial stress in the spring 29, the flyweight 21 is pressed onto the ring 3! and entrains the latter frictionally against the force of the spring 33. The contacts 32 and 44 are separated, so that the current in the coil 26 is interrupted and the brake released. The gearing then transmits no moment of rotation and the dynamo electric machine runs idle.

Thereupon the current flowing through the coil SI is interrupted by opening the switch, and the switch 42 returns into the position indicated in Hg. 7. Consequently the starting circuit of the dynamo electric machine is interrupted, and the coil II is deenergised, sothat the drum II is coupled to the wheel 24 by means ot-the disc 24 pressedthereagainst by the springs 22. As thetoothedrims II and llareheldagainstrelative rotation. it is impossible for the plnions l and lltorollalongthemsothat thedrum I2 I and the wheel l4 and the shaft ll must follow thepinionsupportlcarricdbytheshaiti inits rotation. whereby the whole gearing forms a direct driving connection between the shafts I and II.

The dynamo electric machine is now driven by the internal combustion engine and works as a generator as soon as the diflerence of potential between the terminal 4' and the ground 44 attains the necessary minimum value for closing the automatic switch 4'. In its closing movement the latter opens the auxiliary switch I! and thus prevents the electromagnet II from being switched in again. Hence, the energization of the .clutch and the brake electromagnets, and, as a consequence, the arresting of the drum l2. and the disconnecting of the coupling between the shafts I and II is prevented when the dynamo electric machine works as a generator.

In the embodiment shown in the Figs. 8 and 9 the device for coupling the drum It to the wheel I4 is constructed in such a way as to cause the coupling of the said parts automatically when the coupling electromagnet I9 is energized. The latter then drawsthe armature plate 60 against the friction plate 8| which is rigidly connected to the wheel l4 so that it must follow the latter in its rotation. The armature plate I itself is splined to the drum I! by means of splines 82 which engage grooves In this disposition, the coupling electromagnet II should be energized and the brake electromagnet 20 should remain deenergized during the whole time 01 operation of the machine'as a generator. Therefore, in this example the multi-pole switch 42 controls a separate pair of contacts for each of the electromagnet circuits, namely 84 for the coupling eiectro- 1| magnet l9, and 88 for the brake electromagnet 26. For both said pairs of contacts the switch comprises only one contact bridge 66 so that when the contact 4] in the starting circuit is interrupted, the contact 64 for the coupling electromagnet is closed. In the opposed switch position the starting circuit and the circuit of the brake electromagnet are closed. Since the coupling electromagnet I! must be energized during the current generating operation, a separate switch 61 is provided in its circuit for disconnecting it on stopping the internal combustion engine. Said switch 61 may be combined with the ignition switch of the internal combustion engine. With the exception of the parts which have been speciflcally described, the mechanism and the circuits shown and described in Figs. 8 and 9 correspond to-those which have been described already in connection with Figs. 1 to '7.

The embodiments shown are given by way of example only, and it is to be understood that the basic concept of the invention may be carried out by other forms of mechanism within the scope-of the claims.

WhatI claim is: r

1. Electric starting and generating apparatus 1 for internal combustion engines comprising in combination a dynamo electric machine adapted to function either as a motor or as a generator, a drive member connected to said internal combustion engine, a drive member connected to said dynamo electric machine and substantially coaxial with said other drive member, a gear member rotatable about the common axis of said two drive members, braking means adapted for a'rresting said gear member, coupling means adapted for coupling said gear member to one of said drive members, a toothed rim formed on one of the said three members, a toothed rim formed on another of the said three members, and toothed transmitting gear means in permanent engagement with both said toothed rims, said transmitting gear means being supported on the remaining one oi the said three members.

2. Electric starting and current generating apparatus for internal combustion engines as claimed in claim 1 in which at least one of said teeth rims has internal toothing.

3. Electric starting and generating apparatus for internal combustion engines comprising in combination a dynamo electric machine adapted to function either as a motor or as a generator, a drive member connected to said internal combustion engine, a drive member connected to said dynamo electric machine and substantially coaxial with said other drive member, a gear member rotatable about thecommon axis of said two drive members, braking means adapted for arresting said gear member, coupling means adapted for coupling said gear member to one of said drive members, a toothed rim formed on one of the said three members, a toothed rim formed on another the said three members, a pinion engaging one of the said toothed rims, a pinion engaging the other of said toothed rims, both said pinions being coaxial and angularly coupled to one another and rotatably supported on the remaining one of the said three memberseccentrically to the-common axis of the latter.

4. Electric starting and generating apparatus for internal combustion engines comprising in combination a dynamo electric machine adapted to function either as a motor or as a generator, a pinion supporting member connected in driving relation to said dynamo electric machine, an

internally toothed gearwheel connected in driving relation to said internal combustion engine and coaxial with said pinion supporting member, an internally toothed rotatable member coaxial with said pinion supporting member and said gearwheel, braking means adapted for arresting said rotatable member, coupling means adapted for coupling said rotatable member to said gearwheel, a pinion engaging said gearwheel, a-pinion engaging said rotatable member, both said pinions being angularly coupled to one another and rotatably supported on the said pinion supporting member eccentrically .to the axis of the latter.

5. Electric starting and generating apparatus for internal combustion engines comprising in combination a dynamo electric machine adapted to function either as a motor or as a generator, a drive member connected to said dynamo electric machine and substantially coaxial with said other drive member, a gear. member rotatable about the common axis of said two drive members, a coupling electromagnet, coupling means arranged so as to couple said gear member to one of said drive members when said coupling electromagnet is energized and to uncouple said gear member from said one drive member when said electromagnet is deenergized.

6. Electric starting and generating apparatus for internal combustion engines comprising in combination a dynamo electric machine adapted to function either as a motor or as a generator, a drive member connected to said internal combustion engine, a drivemember connected to said said other drive member, a gear member rotatable about the common axis of said two drive members, a couplingelectromagnet, coupling means arranged so as to couple said gear member to one of said drive members when said coupling electromagnet is energizedand to uncouple said gear member from said one drive member when said coupling electromagnet is deenergized, a braking electromagnet, braking means arranged so as to arrest said gear member when said braking electromagnet is energized and to release said gear member when said braking electromagnet is deenergized, a current source, a switching device, a coupling circuit comprising said current source, said coupling electromagnet and said switching device, a. braking circuit comprising said current source, said braking electromagnet and said switching device, said switching device being arranged so, that in. a first switch position, said braking circuit is closed and said coupling circult is interrupted, and, that in a second switch position said coupling circuit is closed and said braking circuit is interrupted.

7. Electric starting and generating apparatus for internal combustion engines as claimed in claim 6 and comprising an electromagnet adapted for actuating said switching device.

8. Electric starting and generating apparatus :armature winding in said dynamo electric m chine, a starting iield winding connected in series with said armature winding in said dynamo electric machine, a drive member connected to said internal combustion engine, a drive member connected to said dynamo electric machine and substantially coaxial with said other drive member, a gear member rotatable about the common axis of said two drive members, a coupling electromagnet, coupling means arranged so as to couple said gear member to one of said drive members when said coupling electromagnet is energized and to uncouple said gear member from said one drive member when said coupling electromagnet is deenergized, a braking electromagnet, braking means arranged so as to arrest said gear member when said braking electromagnet is energized and to release said gear member when said braking electromagnet is deenergized, a current source, a switching device, a starting circuit comprising said current source, said starting field winding, said armature winding and said switching device, a coupling circuit comprising said current source, said coupling electromagnet and said switching device, a braking circuit comprising said current source, said braking electromagnet and said switching device, said switching device being arranged so that in a first switch position said starting circuit andsaid braking circuit are closed and said coupling circuit is interrupted, and that in a second switch position said coupling circuit is closed and said starting circuit and said braking circuit are interrupted.

10. Electric starting and generating apparatus for internal combustion engines as claimed in claim 6 and comprising a switching electromagnet arranged in such a way that on being energized it moves said switching device into said first switch position, a switching circuit comprising said current source and said switching electromagnet, a relay responsive to the terminal voltage of said dynamo electric machine, said relay being interposed in said switching circuit and adapted to interrupt the latter when said voltage exceeds a predetermined value.

11'. Electric starting and generating apparatus for internal combustion engines comprising in combination a dynamo electric machine adapted to function either as a motor or as a generator, an armature winding in said dynamo electric machine, a starting field winding connected in series with said armature winding in said dynamo electric machine, an auxiliary field winding connected in parallel to said armature winding in said dynamo electric machine, a drive member connected to said internal combustion engine, a drive member connected to said dynamo electric machine and substantially coaxial to said other drive member, a gear member rotatable about the common axis 01' said two drive members, a coupling electromagnet, coupling means arranged so as to couple said gear member to one or said drive members when said coupling electromagnet is energized and to uncouple said gear member from said one drive member when said coupling electromagnet is deenergized; a braking electromagnet, braking means arranged so as to arrest said gear member when said braking electromagnet is energized and for releasing said gear member when said braking electromagnet is deenergized, a battery, a switching device, a starting circuit comprising said battery, said starting ileld winding, said armature winding and said switching device, a coupling circuit comprising said battery, said coupling electromagnet and said switching device, a braking circuit comprising said battery, said braking electromagnet and said switching device, said switching device being arranged so that in a first switch position said starting circuit and said braking circuit are closed and said coupling circuit is interrupted, and that in a second switch position said coupling circuit is closed and said starting circuit and said braking circuit are interrupted, a switching electromagnet arranged in such a way that on being energized it moves said switching device into said first switch position, a relay responsive to the terminal voltage of said dynam'o electric machine, a generating circuit comprising said armature winding, said battery and said relay, a switching circuitcomprising said battery, said switching electromagnet and said relay, said relay being adapted to close the said generating circuit and to interrupt the said switch actuating circuit when thesaid terminal voltage exceeds a predetermined value.

12. Electric starting and generating apparatus for internal combustion engines comprising in combination a dynamo electric machine adapted to function either as a motor or as a generator, a drive member connected to said internal combustion engine, a drive member connected to said dynamo electric machine and substantially coaxial with said other drive member, a gear member rotatable about the common axis of said two drive members, an uncoupling electromagnet, coupling means arranged so as to couple said ear member to one of said drive members when said uncoupling electromagnet is deenergized and to uncouple said gear member from said one drive member when said uncoupling electromagnet is energized, a braking electromagnet, braking means arranged so as to arrest said gear member when said braking electromagnet is energized and to release said gear member when said braking electromagnet' is deenergized, a current source, a switching device, a braking circuit comprising said current source, said braking electromagnet and said switching device, an uncoupling circuit comprising said current source, said uncoupling electromagnet and said switching device, said switching device being adapted to close and to break simultaneously said uncoupling circuit and said braking circuit.

13. Electric starting and generating apparatus for internal combustion engines as claimed in claim 12 and comprising an electromagnet adapted for actuating said switching device.

14. Electric starting and generating apparatus Iorinternal combustion engines as claimed in claim 12 and comprising a switching electromagnet adapted for actuating said switching device, a switching circuit including said switching electromagnet and said current source, and a manually operable switch in said switching circuit.

15. Electric starting and generating apparatus for internal combustion engines comprising in combination a dynamo electric machine adapted to iunction either as a motor or as a generator, an armature winding in said dynamo electric machine, a starting field winding connected in series with said armature winding in said dynamo electric machine, a drive member connected to said internal combustion engine, a drive member connected to said dynamo electric machine and substantially coaxial to said other drive member, a gear member rotatable about the common axis of said two drive members, an uncoupling electromagnet, coupling means arranged so as to couple said gear member to one of said magnet is deenergized, a current source, a switching device, a starting circuit comprising said current source, said starting field winding, said armature winding, and said switching device, an uncoupling circuit comprising said current source, and uncoupling electromagnet and said switching device, a braking'circuit comprising said current source, said braking electromagnet and said switching device, said switching device being adapted to close or to break simultaneously said starting circuit, said uncoupling circuit and said braking circuit.

16. Electric starting and generating apparatus for internal combustion engines as claimed in claim 12 and comprising a switch actuating electromagnet arranged in such a way that on being energized it moves said switching device into its position where said uncoupling circuit and said braking circuit are interrupted, a switching circuit comprising said current source and said switching e1ectromagnet, a relay responsive to the terminal voltage of said dynamo electric machine, said relay being interposed in said switching circuit and adapted to interrupt the latter when said voltage exceeds a predetermined value.

17. Electric starting and generating apparatus for internal combustion engines comprising in combination a dynamo electric machine adapted to function either as a motor or as a generator, an armature winding in said dynamo electric machine, a starting field winding connected in series with said armature winding in said dynamo electric machine, an auxiliary field winding connected in parallel to said armature winding in said dynamo electric machine, a drive member connected to said internal combustion engine, a drive member connected to said dynamo electric machine and substantially coaxial with said other drive member, a gear member rotatable about the common axis of said two drive members, an

uncoupling electromagnet, coupling means arranged so as to couple said gear member to one of said drive members when said uncoupling elec-- tromagnet is deenergized and to uncouple said gear member from said one drive member when said uncoupling electromagnet is energized, a braking electromagnet, braking means arranged so as to arrest said gear member when said braking electromagnet is energized and for releasing said gear member when said braking elec-,

tromagnet is deenergized, a battery, a switching device, a starting circuit comprising said battery, said starting field winding, said armature winding and said switching device, an uncoupling circuit comprising said battery. said uncoupling 'electromagnet and said switching device, a braking circuit comprising said battery, said braking electromagnetand said switching device, said switching device being adapted to close or break simultaneously said starting circuit, said uncoupling circuit and said braking circuit, a

switching electromagnet arranged in such a. way that on being energized it moves said switching device into its position where said uncoupling circuit and said braking circuit are interrupted, a relay responsive to the terminal voltage of said dynamo electric machine, a current generating circuit comprising said armature winding, said battery and said relay, said relay being adapted to close the said current generating circuit and to interrupt the said switch actuating circuit when the said terminal voltage exceeds a predetermined value.

18. Electric starting and generating apparatus for internal combustion engines comprising in combination a dynamo electric machine adapted to function either as a motor or as a generator; a drive member connected to said internal combustion engine; a drive member connected to said dynamo electric machine and arranged substantially coaxially with said other drive member; a gear member rotatable about the common axis of said two drive members; a braking electromagnet; braking means arranged so as to arrest said gear member when said braking electromagnet is energized and to release said gear memberwhen said braking electromagnet is deenergized; a current source; a circuit breaker responsive to the speed of rotation of said electric machine; a braking circuit comprising said current source, said braking electromagnet and said circuit breaker, the latter being constructed so as to break said braking circuit when said dynamo electric machine exceeds a definite speed of rotation. 19. Electric starting and generating apparatus as claimed in claim 5 in which said coupling electromagnet is formed as a stationary coil.

20. Electric starting and generating apparatus for internal combustion engines comprising in combination a'dynamo electric machine adapted to function either as a motor or as a generator, a drive member connected to said internal combustion engine, a. drive member connected to said dynamo electric machine and substantially coaxial with said other drive member, a gear member rotatable about the common axis of said two drive members, an electromagneticaily controlled clutchadapted for coupling said gear member to one of said drive members; electromagnetically controlled braking means adapted for arresting said gear member; a current source; a switching device; a clutch controlling circuit comprising said current source, said electromagnetically controlled clutch, and said switching device; a. brake controlling circuit comprising said current source,

gear member and the clutch to couple said gear member to said one drive member.

ERNST SCHAEREN- switched for the braking means to release said CERTIFICATE OF CORRECTION. Patent No. 2,151,u 7.- March 21, 19 9.

' ERNST SCHAEREN.

It" is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follovys: Page 2, first column, line 1h, for the word "generating" read forminga part of; and ,sec- 0nd column, line 51;, for "wheel 21 read wheel lh; page 5, first column, line 1 8, claim 2, for "teeth rims h s internal toothing" read "toothed rims has internal teeth; same page, second column, line 31;, claim 6, after "said" insert dynamo; line 71;,claim 9, after "function" insert either; page 5, first column, line 2, claim 15, for "not energized" read deenergized; line 1h, same claim, for "and" before "uncoupling" read said; and that the said Letters Patent should be read with this correction therein that the same may conform to the record. of the case in the Patent Office.

Signed and sealed this 2nd day of May, A. D. 1959.

Henry Van Arsdale (Seal) I Acting Commissioner of Patents. 

